From 33cce995560483718045252348b9c075ce6dab40 Mon Sep 17 00:00:00 2001
From: "r@l" <root@localhost>
Date: Tue, 24 Mar 2026 11:28:00 +0100
Subject: [PATCH] Fix single-element tuple Sway syntax to use trailing comma

Sway (like Rust) requires a trailing comma for single-element tuples
to distinguish them from parenthesized expressions: `(T,)` not `(T)`.

* Fix `get_type()` to emit `(T,)` for single-element tuple types
* Fix `get_value()` to emit `(v,)` for single-element tuple values
* Multi-element tuples remain unchanged: `(T, U)` stays `(T, U)`

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---
 src/sway_converter.rs | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/sway_converter.rs b/src/sway_converter.rs
index 81874de..b3dfde5 100644
--- a/src/sway_converter.rs
+++ b/src/sway_converter.rs
@@ -135,7 +135,11 @@ impl SwayConverter {
             ParamType::StringSlice => "str".to_string(),
             ParamType::Tuple(types) => {
                 let values: Vec<String> = types.iter().map(|p| self.get_type(p)).collect();
-                format!("({})", values.join(", "))
+                if values.len() == 1 {
+                    format!("({},)", values[0])
+                } else {
+                    format!("({})", values.join(", "))
+                }
             }
             ParamType::Array(element_type, size) => {
                 let string_element_type = self.get_type(element_type);
@@ -211,7 +215,11 @@ impl SwayConverter {
                     all_values.iter().cloned().unzip();
 
                 (
-                    format!("({})", values.join(", ")),
+                    if values.len() == 1 {
+                        format!("({},)", values[0])
+                    } else {
+                        format!("({})", values.join(", "))
+                    },
                     decls.into_iter().flatten().collect(),
                 )
             }